Synapse Computer Services Plc today launches an On-Line Software Support service for IBM and compatible mainframe users. The Berkhamsted, Hertfordshire company will give users who sign up instant access to the expertise of its 100 or so systems engineers for support and trouble-shooting on all IBM operating systems. The company, which is best known for its conversion products and services, but also offers on-site support, training and applications development services, says it plans to develop the service to covera UK-wide network of offices. The regional support centres will be connected in a ring by high-speed leased lines and customers will link in via dail-up 9600 bps modems. No prices were given for the service. Synapse averages 64% growth over the past eight years.